The invention relates generally to a light collector and more specifically a light collector for coupling light from a light source into a bundle of light pipes.
Elliptical light collectors are generally known for reflecting light from a light source into a light pipe. In general, an ellipse forms the reflecting surface. A light source is placed at one focus of an ellipse and light pipes are placed at the other focus of the ellipse. One disadvantage in such a system is that all the light generated from the light source falls on a single point or a small concentrated area. The region on which concentrated light falls is subject to a build up of heat. Over time, the heat generated can cause deformation and discoloration of the light pipes and lower the efficiency of the light collector.
One example of a modified elliptical collector is described in one embodiment (FIG. 2 (a)) of U.S. Pat. No. 5,222,793. There, a portion of two elliptical reflectors are joined together. The light is concentrated into two focal points, one from each half collector. It is believed that heat concentration divided in two portions is still too intense for many applications.
It would therefore be desirable to provide a light collector for collecting light in several light pipes while maintaining low heat distribution on the face of the light pipes.